Check valve



Dec. 5, 1961 P. w. SANFORD 3,611,517

CHECK .VALVE Filed Dec. 5, 195s PI l 7 l f I3 l? /Z\ O O O O /l MH 4Z I4 44 2z "f 4l 56? 2 fz Q) "5 4g 43 42 46 44\ 4Q 2| 50k- 55 1 A n r( f 4 54 Q3( 41 S/ V 52 M J l/ 47 4.6 JNVENToR.

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United States Patent O 3,011,517 f CHECK VALVE Paul W. Sanford, Indianapolis, Ind., assignor to Tempera Corporation, Portland, Oreg., a corporation of Oregon Filed Dec. 5, 1958, Ser. No. 778,515 2 Claims. (Cl. IS7-533.13)

This invention'relates generally to valves permitting ow in one direction therethrough and l,in-particular to valves of this type adapted to prevent theintroduction of hot water ,or steam into Coldwater service lines.

In my copending applicationv Serial N o. 848,006, filed' Whenever cold and hot water service lines are'brought into proximity with the hot and cold water separated only by a piston or other proportionin-g member, such as in the valve assembly of my copending application or in i various type of mixing-valves., the danger exists that abnormally hot water or steam, caused by malfunctioning of the hot water heating equipment, may by-pass the piston or other proportioning member and enter the cold water service line. The result of such an occurrence is a highly dangerous condition in which scalding hot water may be discharged from cold waterffaucets or other service outlets.

The valve of the present invention is adapted to safeguard against the introduction of steam or abnormally hot water into the cold water service line when used Ywith a proportioning valve as disclosed in my copending application or with various types of mixing valves. It will be understood that while the valve of the present invention is herein described as useful in preventing cross-connection of hot and cold water service lines, it could also be used wherever it is necessary to safeguard against contaminationv of one uid line by another such as in various industrial processes.

A further object of the present invention is to provide a check valve which when installed is coaxial with the pipes into which it is connected, thereby requiring no elbows, offsets orthe like, to complete its installation.

A further object of the present invention is to provide a valve of the type referred to which utilizes aligned outlet apertures whose centers are displaced downstream of the center ofa ball closureto permit ilow through `the valve in one direction, the ball closure being movable against a seat axially spaced from the apertures to prevent iiow through the valve in the opposite direction.

A further objectk of the present invention is to`provide a check valve of the, type herein referred to which is of simple constructionl and is relatively small inioverall dimensions. l

The full vnature of thetinvention will 'be understood i l Ice the check valve of the Referring initially ,to FIG.

.present inventionr is shown generally at 10. "The check cold water inlet fitting 11, a hot water inlet tting 14, a.V

hot water outlet litting 16 and a cold water outlet fitting 17. The central body cavity is provided with a stationary sleeve 18 and a movable piston 19. As pointed out in my copending patent application, the piston 1 9 assumes a position'which proportions they flow of hot water and cold water in response to the pressure balance between the coldu and hot water supply lines 21 and 22, respectively. The hot water outlet fittingl and the cold wateroutlet tting 17 are suitably connected to an apparatus, such as Ia shower head, not shown.

When the proportioning valve 12 is so installed, should a malfunctioning of the hot water heating means cause the presence of abnormally hot water" in the supply pipe 22 or-theV generation of steam therein, the danger exists-that this steam or abnormally hot water might leak past and the land 19a on the piston 19 and enter the cold water inlet fitting 11 and the cold watersunnly line.

The check valve of the present inventioninstalled between the'cold water supply line and the cold water inlet -tting 11, safeguards aga-inst this danger. The check valve includes an elongated tubular housing 41 whichV at' one end receives a threaded female connecting member 42 in turn threaded into the inlet fitting 11 of the propor-` tioning valve-112. The opposite end of the housing ae'- commodates a reducer tting 43 into ywhich is threaded the-cold water suppl-yVV pipe 21.` Thettings'42 and 43- deiine an outlet passage 44 and an inlet passage 46, respectively, at opposite ends of the housing.

A sleeve 47 is disposed within the housing andv extends axially between the inlet passage l46`and the outlet passage 44, the side wall of the sleeve 47 being lspaced from the housing side wall. A spherical closure member or ball 48 is disposed within the sleeve andis freely movable valong the axis of the sleeve, and is sized to provide a piston action in its movement within the sleeve. At the end o f the sleeve -adjacentthe inletfpassage 46, the lfitting 43 is formed so las to provide an inclined seat 49, the ball cooperatingfwith the seat to prevent the ow 'of iluid. 't

At the opposite end ofthe sleeve, thel tting 42 is formed to provide an inclined seat or stop 51 which devfines the extreme upward position of the ball aslwill subsequently be described. The interior o-f the sleeve communicates with the annular space between the `sleeve 'and the housing side wall by means of spaced inletapertures l52. At itsupper end` the sleeve risprovided with a series of aligned voutlet .apertures v53.- As indicated at 54, the plane dened by the centers of the apertures 53 issp'aced:

downstream, or beyond the4 center 'of vthe ballVV 48 when vthe-ball is against the stop 51.

In operation, upon the introduction ot'v fluid under pressure into the `Ycheckvalve through the-pipe 21, the ,ball will initially be moved towar-d its extreme position defined bythe stop 51. Fluid will also ow through apertures 52 and rise in the space between sleeve 47 and housing 41 and-will discharge-in jets throught-he aper-v tures 53. Since the outlet apertures 53 in the sleeve are spaced downstream of the center of the ball ywhen in its extreme upward position, the kinetic energy of the jets issuing from apertures 53 into the sleeve will immediately drive the ball to a position intermediate the ends of the sleeve, this position being indica-ted at 56 in FIG. 1. The ball 48 will retain this mid-position during normal flow conditions. Cold water r similar liuid may then flow freely through the check valve and into the proportioning valve .12. Should withdrawals from the outlet side of the proportioning valve be terminated, causing the pressures on oppositesides of the ball to equalize, the ball will sink under the force of gravity into engagement with the seat 49.

Should the pressure in the outlet passage 42 increase above the pressure in the supply pipe 21 for any reason, such as because of the leakage of live steam across the proportioning valve, theball 48 will be driven tightly against the seat 49 to prevent entry of the steam into the supply pipe 21. The closure of the inlet passage 46 under these conditions is positive in tha-t the greater the pressure exerted on the ball, the tighter it will be seated.

Referring now to FIG. 2, there is shown a modified form o'f the check valve which is identical to that described with reference to FIG. 1 except that it accommodates a tting 42a which replaces the -fitting 42- of FIG. l and permits the check valve to be interposedin a run of pipe. In FIG. 2 parts that are identical with those of FIG. l are given the same reference numerals.

The operation of the modified form is identical to that of the form of FIG. 2, that is, when fluid under pressure is introduced into the inlet passagethe ball 43 initially moves towards its extreme upward .position indicated at 56a and subsequently moves to its intermediate position indicated at 56. Should the pressure in the outlet passage increase beyond that in the inlet passage, the ball will be forced against its seat 49.

The fittings 42 and 413, the ball 48 and the sleeveY 47 are preferably formed of stainless steel so as to have the maximum resistance to corrosion by iluids passing through the check valve. The series o-f inlet apertures 52 and the series of outlet apertures 5135v are preferably sized so that the total area of each series of apertures is substantially equal to the cross sectional area of the inlet passage 46 It should be noted that the check valve of the present invention has relatively small over-all dimensions and can be inserted in a run of pipe coaxially therewith. While the axis of movement of the ball is herein shown and described as being vertical, it will be evident that the valve could be inserted so that the axis of movement is inclined without adversely affecting the functioning of the valve.

While the invention has been disclosed and described in some detail in the drawings and foregoing description, they are to be considered as Villustrative and not Yrestrictive in character, as other modifications may readily suggest themselves to persons skilled in thisart and within the broad scope of the invention, reference being had to the appended claims.

.The invention claimed is:

l. A check valve adapted to permit unobstructed Huid ow in one direction and to seal againstuid tio-w in the opposite direction comprising an elongated, tubular lhousing, provided with an inlet passage and anoutlet passage, said passages being coaxially disposed at opposite ends of saidhousing, a sleeve within said housing Vextending betweeni'said inlet andoutletpassages with the side wall of the sleeve spaced from thev sidel wall of said hous# ing,va spherical closure member Within said sleeve Vand freely movable with a piston action along the axis of said sleeve, a seat for said closure member carried by said housing and disposed at the end of said sleeve adjacent said inlet passage, stop means carried by said housing at the end of said sleeve adjacent said outlet passage and cooperating with said closure member to dene one extreme position of said closure member along said sleeve axis, a series of inlet apertures in said sleeve providing communication between said inlet passage and the space between said sleeve and housing side walls only when said closure member is displaced from said seat, and a series of aligned outlet apertures in said sleeve disposed so that the plane defined by their centersis spaced downstream from the center of said closure member when said closure member is in said one extreme position, said series of inlet apertures and'said series of outlet apertures in said sleeve each having a total area at least equalto the crosssectional area of said inletpassage, whereby upon the introduction of fluid under pressure into said inlet passage said closure member is driven toward said one extreme position and is subsequently driven to a position intermediate the ends of said sleeve, and upon an increase in nid pressure in said outlet passage above that of said inlet passage said closure member is driven into sealing engagement with saidV seat.

2. A check valve adapted to permit unobstructed uid tlow in one direction and to seal against iluid ow in the opposite direction comprising a housing provided with an inlet passage and an outlet passage, said passages being disposed at opposite ends of said housing, a sleeve within said housing extending between said inlet and outlet passages with the side wall of the sleeve spaced from the side wall of said housing, a spherical closure member within said sleeve and freely movable with a piston action l along the axis of said; sleeve, a seat for said closure member disposed at the end of said sleeve adjacent said inlet passage, stop means disposed at the end of said sleeve adjacent said outlet passage and :cooperating with said closure member to define one extreme position of said closure member along said Vsleeve axis, at least one inlet aperture providing communication between said inlet passage and the spacebetween said sleeve and housing side walls only when said closure member is displaced from-said seat, and a series ofV aligned outlet apertures in said sleeve disposed sovthat the plane definedby their centers is spaced downstream from the center of said closure memberl when said closure member is in said one extreme position, said inlet aperture and said series of outlet apertures in said sleeve each having a total area at least equal to the cross-sectional area of said inlet passage, whereby upon the introduction of luid under pressure into said inlet passage said closure member is driven toward said one extreme position and is subsequently driven to a position intermediate the ends of said sleeve, and upon an increase in fluid pressure in said outlet passage above that of said inlet passage said closure member is driven into sealing engagement with said seat.

lReferences Cited in the le of thispatent` UNITED STATES PATENTS' 3,11., king, 

